
html, body{
    width: 100%;
}
.abc{
    margin: 500px;
    width: 50px;
    height: 50px;
}
.abcd{
    background-color: red;
    width: 100%;
}
.abcde {
    margin-left: auto;
    text-align-last: center;
}
.logo{
    height: 79px;
    background-image:url("../img/logo.png");
    background-repeat: no-repeat;
    font-size: 42px;
    font-family: '宋体','黑体','Arial Black';
    color: orange;
}